Cheap pedometers should not be used for public health measures, warn doctors

Cheap step counters otherwise known as pedometers should not be used for public health measures, because they are inaccurate, warn doctors in a report published ahead of print in the British Journal of Sports Medicine.

They base their findings on almost 1000 pedometers, tested out by 35 volunteers between 20 and 60 years of age.

Each volunteer was given 30 cheap pedometers as well as a sophisticated automated step count log against which to compare the performance of the gadgets. They wore five cheap pedometers and the automated step count log each day for a period of six days. They counted the steps recorded daily with each of the pedometers and compared the figures against those of the automated log.

A variation in performance of 10% was considered acceptable, but only one in four of the pedometers fell within this range.

Three out of four either exceeded or fell below 10%. And in more than one in three, the variation was greater than 50%. And in almost two thirds of these, the pedometers overestimated the actual steps taken. This is important, say the authors, because an error of 20% in 10,000 daily steps adds up to 2 000 steps, so either 8 000 or 12 000 steps will be recorded.

Pedometers have become very popular as a cheap and easy way of boosting fitness or losing weight, they say. 'The wide accessibility of pedometers needs encouragement,' they say.

But they warn: 'Inexpensive pedometers provide incorrect information on step counts, which makes them inappropriate for physical activity promotion targets.' And they suggest that a quality kite mark would be helpful for consumers and patients.

Click here to view full paper (PDF 58kb)

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